Tube Lamp with Leadframe

ABSTRACT

A light fixture has a translucent tubular bulb. At least one end cap is located at one end of the translucent tubular bulb. A light engine is disposed in the translucent tubular bulb. The light engine has a leadframe on which a plurality of semiconductor light elements is arranged. The fixture may include an electronic driver. The electronic driver includes a plurality of electronic components. At least one of the plurality of electronic components is arranged inside the transparent tubular bulb.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application is a Continuation of U.S. patent applicationSer. No. 16/232,281, filed on Dec. 26, 2018, which claims priority toEuropean Patent Application No. 18152566, filed on Jan. 19, 2018, whichclaims priority to German Patent Application No. 102017131063.0, filedon Dec. 22, 2017. Each of these patent applications is hereinincorporated by reference in its entirety.

TECHNICAL FIELD

The present invention relates to a tube lamp with a light engine basedon a leadframe, in particular a LED retrofit tube lamp, for example withuse in T5 and T8 lamps.

BACKGROUND

Fluorescent tube lamps are increasingly being replaced by retrofit tubelamps with semiconductor light elements (for example light-emittingdiodes, LEDs). Such retrofit tube lamps usually have a housing in theform of a tubular bulb which is at least partially light-permeable(translucent or transparent), with two end caps at the two ends of thetubular bulb, a light engine which contains a majority of LEDs, and anelectronic driver which supplies the LEDs with electrical energy withthe necessary electrical parameters (current, voltage) for operationthereof.

The term “light engine” is usually used for the arrangement of themajority of LEDs and a holding structure for the LEDs, which containselectrically conductive structures and/or cables by means of which theLEDs can be supplied with electric power by the electric driver.

For the light engine, many retrofit LED tube lamps use a printed circuitboard on which the LEDs are fastened, for example soldered. Such printedcircuit boards are usually produced by etching of a blank which has acopper coat arranged on an electrically non-conductive substrate. Thisresults in a high consumption of copper and correspondingly highproduction costs and strong environmental pollution.

From the German patent application DE 102017109853.4, the disclosure ofwhich is incorporated completely herein by reference, it is known tobuild the light engine of a retrofit tube lamp on a so-called wiringboard. Wiring boards consist of strips of an electrically conductivematerial (for example aluminum), which is laminated between electricallyinsulating, flexible layers (for example polyimide). The requiredcircuit design can then be achieved by stamping out of parts of theelectrically conductive strips. The LEDs can be connected to theelectrically conductive strips by openings in one of the electricallyinsulating layers.

The production of wiring boards with all advantages relative to printedcircuit boards is also elaborate and expensive.

SUMMARY

Starting from the known prior art, it is an object of the presentinvention to provide a light fixture with a simplified light engine.

This object is achieved by a lighting device with the features of theindependent claim. Advantageous further embodiments are set out in thesubordinate claims.

Accordingly, a light fixture is proposed which has a transparent tubularbulb, at least one end cap arranged on an end of the tubular bulb and alight engine arranged in the tubular bulb. According to the invention,the light engine has a leadframe on which a majority of semiconductorlight elements, in particular LEDs, are arranged.

Electrically conductive structures which are stamped or cut out of asheet metal (for example by means of laser cutting or water jet cutting)and function without an electrically insulating substrate (such as aprinted circuit board) or electrically insulating, flexible layers (suchas wiring boards), are designated here as leadframes. For production ofa leadframe the conductive tracks are stamped or cut out of a sheet,wherein transport strips and connection bars for stabilization of thestamped sheet remain for further processing. The transport strips andconnection bars are removed at a later time, for example if theleadframe is sufficiently stabilized by electrical components fastenedthereon.

The fastening of the semiconductor light elements takes place by a SMDsoldering technique (SMD stands for “surface-mounted device”), in whichthe solder points on the stamped out sheet metal parts (conductivetracks) are provided with a soldering paste, then equipped with thesemiconductor light elements and finally are heated by infraredradiation from a melting furnace, whereby the soldering paste melts. Inthis way the semiconductor light elements are connected to theconductive tracks.

The leadframe is a flat structure which has two opposing surfacesextending substantially parallel at a distance of the sheet thickness.The leadframe can be manufactured for example from a cost-effectivematerial, such as for instance steel, or a material with high thermalconductivity, such as for instance copper, or a metal with an opticallyhigh grade appearance, such as brass. The sheet thickness is preferablyin the range from 0.1 mm to 2 mm, more preferably in the range from 0.2mm to 0.8 mm. In particular materials which can be used for printedcircuit boards (PCBs) are suitable. Moreover, the leadframe can becoated for example with a Sn, Zn, Au, Ag, Pt, Pd or Ni layer, and/or thesurfaces of the leadframes can be partially or completely roughened. Thesurfaces of the leadframe can also be coated with a good reflectingcoating, for example with a white or bright color or lacquer layer (inparticular solder resist).

Thus, the production of a leadframe is simpler than that of a wiringboard or a printed circuit board. The conductive structures can also bechosen more flexibly than in the case of a wiring board. The heatdissipation from the semiconductor light elements during operation isimproved by the thermal conductivity of the metallic leadframes.

Within the context of the present disclosure “arranged on the leadframe”means that the corresponding component is fastened to the leadframe andis electrically connected to the leadframe.

The components can be arranged on one surface or on both surfaces of theleadframe. In particular in the case of the semiconductor lightelements, a better all-round transmission of the light can be achievedby equipping the leadframe on both sides.

In one embodiment the light fixture has two end caps which are arrangedat opposing ends of the tubular bulb. Such a light fixture can have T5or T8 models.

In one embodiment the light fixture has precisely one end cap which isarranged at an end of the tubular bulb. The other end of the tubularbulb can be closed by the material of the tubular bulb. Such a lightfixture can for example be configured as a retrofit lamp for a compactfluorescent lamp.

In one embodiment the tubular bulb is closed in a gas-tight manner. Thegas-tight tubular bulb is preferably filled with a filling gas which inparticular has a gas with a high thermal conductivity. The gas with highthermal conductivity can be for example helium, oxygen or hydrogen or amixture of these (for example helium/hydrogen or helium/oxygen). Theremoval of heat from the semiconductor light elements during operationcan be further improved by filling of the tubular bulb with a gas withhigh thermal conductivity.

The filling gas can have further gaseous components by which for examplehigh internal container pressures and/or optical light changes, such aslight filtering and improved light output can be achieved. For example,the filling gas can also comprise nitrogen, argon, air, neon, carbondioxide, nitrogen dioxide or sulfur hexafluoride.

Advantageously, the proportion of the gas with a high thermalconductivity in the filling gas is 1-100%, preferably 50-90%.

In practice the gas pressure in the container is between 0.01 and 1200hPa, wherein a preferred gas pressure is between 0.1 and 1000 hPa.

In one embodiment the light fixture has an electronic driver withseveral electronic components, wherein at least one of the electroniccomponents is arranged inside the tubular bulb. One, several, or allelectronic components can be arranged inside the tubular bulb.Preferably, in particular, electronic components that are expected toemit a gas during operation are arranged outside the tubular bulb. Thisprevents the gas emissions from changing the filling gas present in thetubular bulb and thus possibly changing the characteristics thereof.

A further advantage of the use of a leadframe as a carrier for thesemiconductor light elements is that gas emissions through the carrier(in known light fixtures for example through the printed circuit boardor the wiring board) are substantially reduced.

It is advantageous to arrange as many electrical components of theelectronic driver as possible inside the preferably gas-tight tubularbulb. In this way the components of the light fixture are protected inthe best possible manner against external influences and the lightfixture can be used in surroundings with demanding environmentalconditions, for example as street lighting, in greenhouses, in coastalregions with a high salt content in the air, production environmentswith aggressive gases, etc.

Depending upon the operational environment, the semiconductor lightelements can be selected with a correspondingly suitable spectral range.In this case all semiconductor light elements can emit light insubstantially the same spectral range, or two or more different types ofsemiconductor light elements can be used, for example semiconductorlight elements which emit blue and red light for the illumination ofplants.

In one embodiment at least one of the electronic components arrangedinside the tubular bulb is arranged on the leadframe. In this way theleadframe can ensure the electric connection of the electroniccomponent. As a result, a printed circuit board, on which furtherelectronic components of the electronic driver are arranged, can be assmall as possible. This further decreases possible gas emissions in theinterior of the tubular bulb through the printed circuit board.

In one embodiment, the leadframe has a central region on which themajority of semiconductor light elements is arranged and at least oneend region on which at least one of the electronic components of theelectronic driver is arranged. As a result, in particular, theelectronic components of the electronic driver, which are larger thanthe semiconductor light elements, are arranged at the ends remote fromthe semiconductor light elements, where they hinder the emission oflight through the semiconductor light elements as little as possible.

However, electronic components of the electronic driver can also bearranged in the central region of the leadframe. If the electroniccomponents of the electronic driver are arranged in both end regions ofthe leadframe, the leadframe can have additional connecting sectionswhich connect the two end regions electrically.

In order to prevent such connecting sections, which extend over theentire length of the leadframe, from causing undesirable electromagneticinterference (EMI), these connecting sections can be connected toadjacent sections of the leadframe at one or more locations by means ofcapacitors. This procedure is described for example in the German patentapplication DE 102017103184.7, the disclosure of which is incorporatedcompletely herein by reference.

In one embodiment, the width of the leadframe in at least one end regionis greater than the width of the leadframe in the central region. As aresult there is sufficient space available for the electronic driver,whilst the central region with the semiconductor light elements can beas narrow as possible. For reasons of material saving (environmental andcost advantages) it is advantageous to design the central region to beas narrow as possible. For example, the width of the leadframe in thecentral region is between approximately 6 mm and approximately 10 mm,preferably between approximately 7 mm and approximately 8 mm. Inparticular, if no connecting sections are required for parts of theelectronic driver in both end regions of the leadframe, the width of thecentral region can be approximately 7 mm. With additional connectingsections the width of the central region can reach up to approximately10 mm.

In one embodiment the width of the leadframe is variable over itslength. In particular the width of the leadframe can change linearly,preferably continuously linearly, over the length, for example from afirst width at a first end of the leadframe to a second width which issmaller than the first width at a second end of the leadframe. As aresult, sufficient space can be provided at the wider end of theleadframe for the electronic driver.

Furthermore, an embodiment of the leadframe with a continuously linearlychanging width has the advantage that several leadframes can be producedwithout cutting-waste from a starting material, in that a narrow end anda wide end of neighboring leadframes are alternately arranged adjacentto one another.

Manufacture of several leadframes without cutting-waste from a startingmaterial can also be achieved if only one of the end sections of theleadframe is wider than the central section, and preferablyapproximately twice as wide as the central section. Then during themanufacture the wide end section of the first, third, etc. leadframescan be arranged adjacent to one another on one side and the wide endsections of the second, fourth, etc. leadframes can be arranged on theother side, that is to say the corresponding leadframes are rotated by180°.

In one embodiment the electronic driver is a linear driver. Lineardrivers for LED lamps are known for example from the internationalpatent applications WO 2007/144365 A1 and WO 02/23956 A2, the disclosureof which is incorporated completely herein by reference. The lineardrivers disclosed in these publications can also be used in embodimentsof the light fixture according to the invention.

A linear driver has the advantage that it functions with very fewelectronic components. The core piece of the linear driver is a currentregulator which is usually available as an integrated circuit (IC). Inthe above-mentioned publications a transistor or a LM317AT from NationalSemiconductor can be used as current regulator. As an alternative aBP5151HC from Bright Power Semiconductor Co. can be used.

In a linear driver attention must be paid to a good cooling, inparticular in the case of a current regulator. Preferably, therefore,the current regulator is arranged on the leadboard, whereby the heatgenerated by the current regulator in operation can be easilydissipated.

In one embodiment the electronic driver is embedded in a fillingmaterial. The filling material can comprise a polymer (for examplecasting resins and/or highly viscous adhesives made of silicone,polyurethane, polyacrylic, polyester, polyamide, polyolefin and/orepoxy) and/or a filler (for example glass beads, sand, lime, ceramicpowders such as for example Al₂O₃ or a mixture thereof). The polymermass can be translucent (in particular transparent). Furthermore, thedriver embedded in the filling material can be provided with a sealingcoat (for example polymer). The polymer mass can cure under the effectof temperature, UV, moisture and/or time.

The heat-conducting connection of the electronic driver into the glassbulb can be improved by embedding of the electronic driver in such afilling material (potting). In particular the heat generated by thecurrent regulator and/or by the capacitor in operation can be dissipatedbetter onto the wall of the glass bulb and onto the end cap.

Furthermore, possible gas emissions from the electronic components canbe isolated from the light engine with the semiconductor light elementsby the potting of the electronic driver. This may be of interest, inparticular, in the case of electrolyte capacitors used as smoothingcapacitors.

Such potted electronic drivers are preferably arranged at one end (i.e.only in one end cap) in the lamp, since the filling operation can takeplace on the lamp which is closed at one end by gravity. In this casethe electronic driver can be positioned both on the leadframe and alsoon a separate printed circuit board.

In the case of the separate printed circuit board, the electronic drivercan also be pre-potted outside the lamp in order to surround theelectronic components and to reduce possible gas emissions from theelectronic components and the separate FR4 printed circuit board.Independently of this, the pre-potted driver can also be connected tothe glass bulb by means of a subsequent further potting process.

In a further embodiment the lamp interior is also filled in the regionof the semiconductor light elements with a translucent (in particulartransparent) filling material (for example glass beads, glitteringacrylic rhinestones with diamond effect, polymer granulate or a mixturethereof). In this way may the heat dissipation can be improved and thevisual appearance of the light fixture can be influenced. Such anembodiment can have a particularly high-quality appearance. Moreover, itis possible to dispense with applying a slurry or internal matting ofthe glass bulb, which is normally carried out in order to render theinterior of the lamp invisible from the exterior.

In order to save on weight and filling material, a partial coating ofthe bulb by such a translucent filling material (optical diffuserparticles) can be carried out. In this case the bulb can be inclined andcan be filled with a mixture of casting resin/adhesive with opticalfillers (glass beads, ceramic powder, acrylic rhinestone-glitter stoneswith diamond effect, etc.). In this case, the low-viscosity castingresin/filler mixture runs downwards on the side opposite thesemiconductor light elements (i.e. on the side towards which the lightis emitted). In this case the lamp is preferably closed at one end andthe electronic driver can be arranged at the bottom with regard togravity and thus can be simultaneously embedded in the filling material.Alternatively, the lamp can also be initially filled with thelow-viscosity pure casting resin/adhesive, followed by slight hardeningso that the casting resin/adhesive becomes highly viscous, and finallythe optical diffuser particles can be introduced which remain adhered onthe highly viscous casting resin/adhesive strip.

Alternatively or in addition to casting resins and/or polymer adhesives,so-called hotmelt adhesives can also be used, i.e. adhesives which areinitially present in solid form, for example as powder or granulate, andonly become liquid when heated.

In this case the filling operation can take place completely by means ofsolid materials (hotmelt granulate and fillers such as glass beads,sand, lime or ceramic powder).

The connection to the glass bulb and/or the electronic components takesplace by subsequent heating, so that the hotmelt adhesive is melted.

Since hotmelt adhesives and polymer masses (polymer casting resin,polymer adhesive) are more expensive than the fillers, the quantity ofholtmelt adhesive or polymer mass can be kept as small as possible bymeans of a 3-stage method:

-   -   1. Introduction of the pure fillers into the driver region of        the lamp which is closed at one end,    -   2. Introduction of the hotmelt granulate onto the filler        granulate.    -   3. Melting of the hotmelt sealing coat and sealing of the driver        region.

This has the further advantage that the melting of the hotmelt sealingcoat takes place spatially separately from the electronic components. Inthe ideal case the sealing coat is merely in contact with thetemperature-resistant leadframe metal, the temperature-resistant softglass enveloping bulb and the temperature-stable filling material (glassbeads, sand, etc.).

In one embodiment the leadframe has one or more projections, inparticular deep-drawn sections, embossings, etc. The projections can belocated on the underside of the leadframe, i.e. on the surface on whichno semiconductor light elements are arranged. On the top side of theleadframe, i.e. on the surface on which the semiconductor light elementsare arranged, the projections then appear as depressions. In the regionof the projections, i.e. substantially around the projections on theunderside of the leadframe and/or on the projections, the leadframe canbe provided with an adhesive by which the leadframe is fastened to theinside of the tubular bulb.

The projections reduce the spacing between the leadframe and the innersurface of the tubular bulb, so that a smaller quantity of adhesive isrequired when the leadframe is adhered to the tubular bulb at theselocations.

The spacing between two semiconductor light elements is usuallyapproximately 17 mm. In order to achieve a sufficient number of adhesionpoints, the spacing between two depressions can correspond to 2, 3, 4 or5 times the spacing between the semiconductor light elements, inparticular approximately 34 mm, 51 mm, 68 mm or 85 mm. Other spacingsare also possible. The projections can also be unevenly distributedalong the light engine.

Alternatively or in addition the leadframe can be fastened by means ofretaining clips which are fastened to the inside of the tubular bulb.Such retaining clips are known from the international patent applicationWO 2011/064305 A1, the disclosure of which is incorporated completelyherein by reference.

In one embodiment the leadframe has bent sections which can be producedby stamping on one side and bending. These can enlarge the coolingsurface for electronic components which are subject to high thermalload.

Furthermore, the leadframe can be fastened to the inside of the tubularbulb by means of laser welding. In this case, at locations at which theleadframe abuts the inside of the bulb the leadframe is heated point bypoint by means of a laser through the glass of the bulb. The heat istransmitted to the glass and the glass is melted. In this way theleadframe is fused with the glass.

The material of the leadframe is preferably selected so that—in additionto the necessary electrical conductivity and solderability—it has asimilar coefficient of thermal expansion to the glass of the tubularbulb. For example, the tubular bulb can be made from a conventionalsoda-lime glass with a coefficient of thermal expansion of approximately9.8 ppm/K and the leadframe can be made from DC01 steel with acoefficient of thermal expansion of approximately 10.5 ppm/K. In thecase of a light fixture having a length of 1.5 m at a temperaturedifferent from 100 K (for example −20° C. to 80° C.) the difference of0.7 ppm/K corresponds to a difference in the longitudinal dimension ofapproximately 0.1 mm. Such a difference can be compensated for withoutproblems by the aforementioned fastening methods. As a result, inparticular, the direct adhesion of the leadframe onto the inside of thetubular bulb is made possible.

In one embodiment the electronic driver has a printed circuit board onwhich at least one of the electronic components is arranged. Thus theelectronic components of the electronic driver can be all arranged onthe printed circuit board, all arranged on the leadboard or can bearranged partially on the printed circuit board and partially on theleadboard. The printed circuit board can be arranged completely insidethe tubular bulb or at least partially in an end cap of the lightfixture.

The printed circuit board can be connected to the leadframe by means ofat least one electrically conductive connecting element.

Two printed circuit boards for electronic components of the electronicdriver can also be provided, wherein each printed circuit board can bearranged completely inside the tubular bulb or at least partially in anend cap of the light fixture. The electronic components of theelectronic driver can then be distributed over the two printed circuitboards. Accordingly, two electrically conductive connecting elements arethen provided for connection between the printed circuit board and theleadframe.

It may also be provided that a first printed circuit board is arrangedcompletely inside the tubular bulb (which is possibly closed gas-tight)and a second printed circuit board is arranged outside the tubular bulbat least partially in an end cap of the light fixture. As a result,electronic components which exhibit undesirable gas emission can bearranged outside the tubular bulb, whilst the other electroniccomponents are arranged in the interior of the tubular bulb, where theyare protected against environmental influences.

In one embodiment the leadframe has a bent section which serves as aconnecting element. To that in particular one of the stamped-out orcut-out metal surfaces of the leadframe can be bent at least partiallyinto the shape of a connecting element. The material used for theleadframe can have spring characteristics which ensure that the bentpart of the leadframe presses against corresponding contact areas on theprinted circuit board.

In one embodiment the light engine also has an electrically conductivemeans, in particular a cable, which extends from a first end of theleadframe or a printed circuit board arranged on the first end of theleadframe to a second end of the leadframe or to a printed circuit boardarranged on the second end of the leadframe. As a result, an electricalconnection can be achieved between the two ends of the leadframe orbetween sections of the electronic driver arranged on both ends, withoutthe provision of corresponding sections therefor in the leadframe. Thismakes it possible to make the leadframe extremely narrow.

Furthermore, in one embodiment the light engine has one or morestabilizing sections which are made from an insulating material andwhich are introduced locally, preferably in a punctiform and/or linearmanner, into intermediate spaces of the leadframe in order to fastensections of the leadframe to one another and preferably to space themapart from one another.

In this connection “locally” means, in particular, that the leadframe isnot completely or for the most part embedded in a housing or a shell,for instance made from plastics material. The stabilizing sections arecharacterized in that they are provided locally at points on theleadframe at which a stabilization and optionally a spacing is necessaryin order to ensure the mechanical and electrical functionality of theLED module. Thus the stabilizing sections can be provided, inparticular, in spaces, for instance gaps, so as to prevent aninadvertent bending together and contacting of sections of the leadframewhich are to be insulated electrically.

The stabilizing sections are preferably manufactured from polymer and/orglass and/or ceramic and/or cement and/or SMD components with insulatingproperties. SMD components with insulating properties comprise:resistors with an extremely high resistance in the mega- or giga-ohmrange; diodes in locking direction; capacitors in direct currentapplications or the like. Epoxy resin adhesive has proved to beadvantageous as a polymer, of which the coefficient of thermal expansionis in the same order of magnitude as a possible polymer housing ofsemiconductor light elements such as LEDs and thus, in the event ofchanging temperature load, causes no thermal stresses on thesemiconductor light elements. Alternatively or in addition, otherpolymers may also be considered, such as for instance thermoplastics,for example PC, PMMA, PBT, thermosetting plastics or elastomers, such asfor example silicones.

In this way the leadframe of the light engine is stabilized particularlywell so that, even after the removal of the initially stabilizingconnecting webs, it can be readily manipulated during the installationin the tubular bulb.

Such stabilization can be advantageous, in particular, where longersections of the leadframe extend alongside one another without beingconnected to one another by means of electronic components (such ascomponents of the electronic driver or capacitors for reduction ofelectromagnetic interference emissions).

The two surfaces of the leadframe preferably for the most part have nocontact with material of the stabilizing sections. “For the most part”,in this use, means that more than half, preferably more than 80%, ofboth surfaces (considered individually) are not in contact withstabilizing sections. Preferably both surfaces (considered individually)of the leadframe are (in the sense defined above) uncovered, i.e.moreover they also have no contact with LEDs, SMD components, solderpoints etc. This, in particular, improves the heat dissipation via theleadframe onto the gas located in the tubular bulb.

For the same reasons, the individual stabilizing sections are preferablydistinguishable, i.e. they do not overlap to form a structure in theorder of magnitude of the leadframe. Accordingly, the expansion of theindividual stabilizing sections preferably corresponds to only a smallpart of the overall expansion of the leadframe. In particular, theleadframe preferably has electrically insulating intermediate spaces,for instance gaps or gap sections, which are not filled and thuscompletely penetrate the leadframe in the direction of the thickness.The expansion of the stabilizing section preferably correspondssubstantially to the order of magnitude of the intermediate spaces to bebridged.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred further embodiments of the invention are explained in greaterdetail by the following description of the drawings. In the drawings:

FIG. 1 shows an embodiment of a tube lamp according to the presentinvention;

FIG. 2 shows a schematic representation of the electrical circuit of theLEDs in the embodiment according to FIG. 1;

FIG. 3 shows an embodiment of the connection between the printed circuitboard and the leadframe;

FIG. 4 shows schematically an arrangement of several leadframes of anembodiment during the production;

FIG. 5 shows schematically an arrangement of several leadframes of afurther embodiment during the production;

FIG. 6 shows schematically an arrangement of several leadframes of afurther embodiment during the production;

FIG. 7 shows schematically an arrangement of several leadframes of afurther embodiment during the production;

FIG. 8 shows schematically an arrangement of several leadframes of afurther embodiment during the production;

FIG. 9 shows schematically an arrangement of several leadframes of afurther embodiment during the production;

FIG. 10 shows a schematic representation of the electrical circuit of alinear driver for the LEDs;

FIG. 11 shows schematically an arrangement of several leadframes of afurther embodiment during the production;

FIG. 12 shows schematically a side view of a leadframe corresponding toFIG. 11;

FIG. 13 shows schematically a leadframe with an additional connectingcable;

FIG. 14 shows schematically an arrangement of several leadframes of afurther embodiment during the production;

FIG. 15 shows schematically an arrangement of several leadframes of afurther embodiment during the production;

FIG. 16 shows an embodiment of a light fixture with a leadframeaccording to FIG. 15;

FIG. 17 shows schematically an embodiment of a first end region of aleadframe;

FIG. 18 shows schematically an embodiment of a second end region of aleadframe;

FIG. 19 schematically the first end region of a leadframe according toFIG. 17 with electronic components in a light fixture;

FIG. 20 shows schematically the first end region of a leadframeaccording to FIG. 17 without electronic components in a light fixture.

DETAILED DESCRIPTION

Preferred exemplary embodiments are described below with reference tothe drawings. In this case elements which are the same, similar, or actin the same way are provided with identical reference numerals in thedifferent drawings, and repeated description of some of these elementsis omitted in order to avoid redundancies.

An embodiment of a tube lamp according to the invention is partiallyshown in FIG. 1. The tube lamp has a light-permeable tubular bulb 1, andon the two ends an end cap 2 is arranged. Two connecting pins 3, retainthe tube lamp in a corresponding socket and supply the tube lamp withelectrical power, are fastened in the end cap.

In the interior of the end cap 2 and extending from there into theinterior of the tubular bulb 1 there is an electronic driver 4, of whichthe electronic components 5 are arranged on a printed circuit board 6.The driver 4 is retained securely in the interior of the tube lamp bymeans of a retaining bar 7 on the inside of the tubular bulb 1.

A leadframe 8 on which several light-emitting diodes (LEDs) 9 arearranged can be used as a light engine. The leadframe 8 comprisesseveral sections 10 which have been stamped out or cut out of a sheetmetal (for example DC01 steel).

In the illustrated embodiment the leadframe 8 has substantially threeparallel strips, wherein the first strip 11 (shown in the drawing as therear strip) and the second strip 12 (shown in the drawing as the middlestrip) are in each case composed of several sections 10. On the otherhand, the third strip 13 (shown in the drawing as the front strip) iscontinuous over the length of the leadframe 8. In this case thedesignations “front”, “middle” and “rear” relate to the representationin the drawing and are used below synonymously with the “first”,“second” and “third” strip. The sections 10 of the rear strip 11 and themiddle strip 12 are arranged offset with respect to one another, so thatin each case they overlap by half a section 10. Between the right-handregion (in the drawing) of a section 10 of the rear strip 11 and theleft-hand region (in the drawing) of a section 10 of the middle strip 12two LEDs 9 are parallel-connected to one another. Between the right-handregion (in the drawing) of a section 10 of the middle strip 12 and theleft-hand region (in the drawing) of a section 10 of the rear strip 11two LEDs 9 are likewise parallel-connected to one another, so that thefirst-mentioned group of parallel LEDs and the second group of parallelLEDs are connected in series. This pattern continues over the length ofthe leadframe 8.

The first (left-hand) section of the rear strip 11 is connected to afirst output terminal of the electronic driver 4. The last pair with twoparallel LEDs 9′ (not shown in FIG. 1, but visible in FIG. 4) isconnected to the right-hand section of the middle strip 12 and to thefront (continuous) strip 13. As a result, the connection to a secondoutput terminal of the electronic driver 4 is achieved and the currentcircuit is closed. Instead of two LEDs, a 0-ohm resistor or anotherconductive element can be used for the connection between the middlestrip 12 and the front strip 13. Alternatively or in addition, one ormore connection bars can be retained for closure of the current circuit,i.e. during separation of the individual sections of the leadframe theseconnection bars are not severed.

Thus the LEDs are arranged as a series connection of parallel-connectedpairs of LEDs, as shown schematically in FIG. 2.

FIG. 3 shows an embodiment of the connection between the printed circuitboard of the electronic driver 4 and the leadframe 8. Two contact clips26 are in each case fitted with a substantially U-shaped contact region14 onto the printed circuit board 6 of the driver 4 so that on theprinted circuit board 6 the U-shaped contact regions 14 contactcorrespondingly arranged contact points which constitute the two outputterminals of the driver 4. Connection regions 27, which contactcorresponding sections 10 of the leadframe 8, extend from the lowerbranch of the U-shaped contact region 14. As a result, an electricalconnection between the printed circuit board of the electronic driver 4and the leadframe 8 is produced.

Alternatively here, the left-hand end (in the drawing) of the frontstrip 13 and of the first (left-hand) section of the rear strip 11 arebent so that two substantially U-shaped contact regions 14 are produced,into which the printed circuit board 6 of the driver 4 is inserted. Thenon the printed circuit board 6 the U-shaped contact regions 14 contactcorrespondingly arranged contact points which constitute the two outputterminals of the driver 4. As a result the corresponding sections 10 ofthe leadframe 8 assume the function of the contact clips 26.

FIG. 4 shows schematically an arrangement of several leadframes 8, suchas can be used in an embodiment of a light fixture according to FIG. 1or in other embodiments, during the production. The leadframes 8 havebeen stamped out or cut out from a plate 15 (for example by means oflaser cutting) and are still connected by means of connection bars 16 toa frame 17 and to one another. Four leadframes 8 are shown in FIG. 4,but a different number of leadframes 8 can be produced from one plate15.

Each leadframe 8 has three strips, an upper strip 11 (corresponding tothe first strip or rear strip in FIG. 1), a middle strip 12(corresponding to the second strip or middle strip in FIG. 1) and alower strip 13 (corresponding to the third strip or front strip in FIG.1). In this case the designations “upper”, “middle” and “lower” relateto the representation in the drawing and are used below synonymouslywith the “first”, “second” and “third” strip.

The upper strip 11 and the middle strip 12 are in each case composed ofseveral sections 10. The lower strip 13 is continuous over the length ofthe leadframe. The sections 10 of the upper strip 11 and the middlestrip 12 are arranged offset with respect to one another, so that ineach case they overlap by half a section 10. Between the right-handregion (in the drawing) of a section 10 of the upper strip 11 and theleft-hand region (in the drawing) of a section 10 of the middle strip 12two LEDs 9 are parallel-connected to one another. Between the right-handregion (in the drawing) of a section 10 of the middle strip 12 and theleft-hand region (in the drawing) of a section 10 of the upper strip 11two LEDs 9 are likewise parallel-connected to one another, so that thefirst-mentioned group of parallel LEDs and the second group of parallelLEDs are connected in series. This pattern continues over the length ofthe leadframe 8. For reasons of clarity, not all of the LEDs 9 areshown.

The last pair with two parallel LEDs 9′ is connected to the right-handsection of the middle strip 12 and to the lower (continuous) strip 13.Instead of two LEDs, a 0-ohm resistor or another conductive element canbe used for the connection between the middle strip 12 and the lowerstrip 13. Alternatively or in addition, one or more connection bars 16can be retained for closure of the current circuit, i.e. duringseparation of the individual sections of the leadframe 8 theseconnection bars 16 are not severed.

Stabilizing sections can be provided between the sections 10 and/orbetween the strips 11, 12, 13 of the leadframe 8 for stabilization ofthe leadframe 8. In particular, the continuous lower strip 13 ispreferably connected locally to the adjacent middle strip 12 bystabilizing sections (insulating material or insulating SMD components).

When all LEDs 9 are mounted on the leadframe 8 and are connectedthereto, the connection bars 8 can be severed and the leadframes 8 canbe separated from the frame 17 and from one another.

The width of the leadframe 8 is preferably approximately 7 mm. Thussufficient space is available for the LEDs 9 on the leadframe 8 withoutunnecessarily requiring material for the leadframe 8. The width of theupper strip 11 and the middle strip 12 is preferably approximately(2.0±0.1) mm. The width of the lower strip 11 is preferablyapproximately (1.6±0.1) mm. The width of the stamped openings betweenthe strips is preferably (0.7±0.1) mm. The width of the stamped openingsbetween the sections 10 in one strip is preferably (1.0±0.1) mm. Thelength of the sections 10 of the upper strip 11 and the middle strip 12is preferably approximately (67.6±0.5) mm. The length of the leadframe 8is preferably 17 sections 10, i.e. approximately 1166 mm. Thus in a lampwith an overall length of 1200 mm (also called a 4-foot lamp) spacestill remains for an electronic driver. If a stamping tool which isshorter than the leadframe is to be used a number of times, theleadframe can also be produced first of all with a length of 18 sectionsand a section can be removed later. For reasons of better identificationfewer sections are shown in the drawing. The above-mentioned dimensionscan also be used in the subsequent leadframes.

Thus with four LEDs per section there are 66 or 68 LEDs, depending uponwhether the connection between the middle strip 12 and the lower strip13 takes place by two LEDs 9′ or by a 0-ohm resistor. With an operatingvoltage of 3 V per LED this produces an overall operating voltage of 198V or 204 V. Such a voltage can be generated for example by a lineardriver.

In the embodiment according to FIG. 4 the first section (on the left inthe drawing) of the upper strip 11 has a length which corresponds to ¾of the length of the further sections 10. The last section (on the rightin the drawing) of the upper strip 11 likewise has a length whichcorresponds to ¾ of the length of the further sections 10. The firstsection (on the left in the drawing) of the middle strip 12 has a lengthwhich corresponds to ¼ of the length of the further sections 10.Correspondingly the last section (on the right in the drawing) of themiddle strip 12 likewise has a length which corresponds to ¼ of thelength of the further sections 10.

However, the first sections (on the left in the drawing) and/or the lastsections (on the right in the drawing) can also be designed to belonger, which can simplify the connection to the driver, in particularwhen end sections of the leadframe are converted into contact regions(see FIG. 3).

FIG. 5 shows schematically an arrangement of a plurality of severalleadframes 8 in a further embodiment during the production. Eachleadframe 8 has a central region 18 and an end region 19.

The central region 18 of the leadframe 8 in FIG. 5 corresponds to theleadframe illustrated in FIG. 4 and is not explained again here.However, other configurations of the leadframe in the central region 18can be used.

The end region 19 of the leadframe 8 is provided for electroniccomponents 5 of the driver 4. The precise division of the end region 19into leadframe sections depends upon the design of the driver 4 and istherefore not illustrated in detail here.

The width of the leadframe 8 is preferably approximately 7 mm. Thussufficient space is available for the LEDs 9 and the electroniccomponents 5 of the driver on the leadframe 8 without unnecessarilyrequiring material for the leadframe 8.

FIG. 6 shows schematically an arrangement of several leadframes 8 in afurther embodiment during the production. Each leadframe 8 has a centralregion 18 and two end regions 19, 20.

The end regions 19, 20 of the leadframe 8 are provided for electroniccomponents 5 of the driver 4. The precise division of the end regions19, 20 into leadframe sections depends upon the design of the driver 4and is therefore not illustrated in detail here. An embodiment of thedivision of the end region of the leadframe 8 is illustrated by way ofexample in FIGS. 17 to 20. The division of the driver 4 over two endregions 19, 20 makes it possible to design the end regions 19, 20 ineach case to be smaller and so to distribute the non-luminous regionover the two ends of the light fixture.

The central region 18 of the leadframe 8 in FIG. 6 correspondssubstantially to the leadframe illustrated in FIG. 4 and in this respectis not explained again here. However, other configurations of theleadframe in the central region 18 can be used. In addition, to thesection of the leadframe 8 taken from FIG. 4 (i.e. the three upperstrips 11, 12, 13) the leadframe has two further strips 21 which servefor connection of the two parts of the electronic driver 4.

The strips 21 are preferably connected to one another and/or areconnected locally to the adjacent lower strip 13 by stabilizing sections(insulating material or insulating SMD components). Stabilization cantake place in particular by capacitors which can prevent or at leastreduce undesirable electromagnetic interference.

The width of the leadframe 8 is preferably approximately 10 mm. Thussufficient space is available for the LEDs 9 and the electroniccomponents 5 of the driver on the leadframe 8 without unnecessarilyrequiring material for the leadframe 8. The additional strips 21 giverise to a wider configuration of the leadframe 8 by comparison with thepreceding embodiments.

FIG. 7 shows schematically an arrangement of several leadframes 8 in afurther embodiment during the production. Each leadframe 8 has a centralregion 18 and an end region 19.

The end region 19 of the leadframe 8 is provided for electroniccomponents 5 of the driver 4. The precise division of the end region 19into leadframe sections depends upon the design of the driver 4 and istherefore not illustrated in detail here.

The end region 19 is twice as wide as the central region 18, so that inthe end region 19 more space is available for the electronic components5 of the driver 4. The width of the central region 18 of the leadframes8 is preferably approximately 7 mm, and thus the width of the end regionis approximately 14 mm. Thus sufficient space is available for the LEDs9 and the electronic components 5 of the driver on the leadframe 8without unnecessarily requiring material for the leadframe 8.

The leadframes 8 in which the end region 19 is arranged on the left-handside (in the drawing) correspond to the leadframes according to FIG. 5(apart from the width of the end region 19). By comparison, theleadframes 8 in which the end region 19 is arranged on the right-handside (in the drawing) are rotated by 180°.

FIG. 8 shows schematically an arrangement of several leadframes 8 in afurther embodiment during the production. In particular, the width ofthe leadframes 8 is reduced from a first width at a first end of theleadframe 8 to a second width which is smaller than the first width at asecond end of the leadframe 8. The width at the second end is preferablyno more than approximately 7 mm, more preferably no more thanapproximately 5 mm. The width at the first end is preferablyapproximately 20 mm. As a result sufficient space can be provided at thewider end of the leadframe for the electronic driver.

For reasons of clarity, the division of the leadframe 8 into sections 10is not illustrated here.

FIG. 9 shows schematically an arrangement of several leadframes 8 in afurther embodiment during the production. The arrangement of the strips11, 12, 13 and sections 10 of the leadframe 8 corresponds substantiallyto the arrangement according to FIG. 4. In addition to the LEDs 9electronic components 5 of the driver 4 are arranged here in the regionof the light engine using the division of the two upper strips 11, 12into sections 10.

A linear driver such as shown schematically in FIG. 10 can be used as anelectronic driver 4. The electronic driver has a rectifier consisting offour diodes D, at the output of which a smoothing capacitor C1 isprovided. A connection of the smoothing capacitor C1 is connected toearth. An integrated circuit IC of the BP5151HC type can be used for thelinear driver. The connection CS of the integrated circuit IC isconnected to earth by means of a resistor R1. The connection VD of theintegrated circuit IC is connected to earth by means of a capacitor C2.Furthermore, the connection VD of the integrated circuit IC is connectedby means of a resistor R2 to the cathode end of the series-connectedLEDs. The drain connection of the integrated circuit IC is connecteddirectly to the cathode end of the series-connected LEDs. The connectionGND of the integrated circuit IC is connected to earth.

The integrated circuit IC of the BP5151HC type is usually obtainable inthe form of the ESOP8 model, as also illustrated in FIG. 10. In thiscase the four connectors NC have no function. If the integrated circuitwith the same functionality is used in the SOT223 or TO252 model, asshown in FIG. 9 it can be arranged together with the resistors R1 and R2and the capacitor C2 directly in the region of the light engine on theleadframe.

The rectifier and the smoothing capacitor C1 (not shown in FIG. 9) canthen be arranged in one or two end regions of the leadframe or on aseparate printed circuit board.

FIG. 11 shows schematically an arrangement of several leadframes 8 in afurther embodiment during the production. The leadframes 8 correspondsubstantially to the leadframes according to FIG. 4.

Approximately in the center of each section 10 of the middle strip 12 adepression 22 (viewed from the top face of the leadframe 8) is provided,which can be provided for example by embossing or deep drawing. FIG. 12shows schematically a side view of a leadframe 8 with depressions 22(again without LEDs) in a tubular bulb 1. The depressions 22 or theprojections produced thereby on the other side of the leadframe 8 serveto reduce the spacing between the leadframe 8 and the inside of thecurved tubular bulb 1. In this way a narrow adhesive gap is producedwhich reduces the quantity of adhesive to be used.

FIG. 13 shows schematically a leadframe 8 in a further embodiment. Theleadframe 8 corresponds substantially to the leadframes according toFIG. 4, but does not have a lower strip 13. The electrical connectionbetween the right-hand end (in the drawing) of the leadframe 8 and adriver (not shown) on the left-hand end of the leadframe can take placefor example with a (schematically indicated) cable 23.

FIG. 14 shows schematically an arrangement of several leadframes 8 in afurther embodiment during the production. The leadframes 8 correspondsubstantially to the leadframes according to FIG. 4.

The three strips 11, 12, 13 of the leadframes 8 are connected to oneanother by stabilizing sections 24 made of insulating material, wherebythe stability of the leadframes 8 is increased. Apart from theillustrated arrangement, the stabilizing section 24 can also be used forother arrangements. For reasons of clarity, not all of the stabilizingsections 24 are illustrated.

FIG. 15 shows schematically an arrangement of several leadframes 8 in afurther embodiment during the production. Each leadframe 8 has twostrips, an upper strip 11 and a lower strip 12. In this case thedesignations “upper” and “lower” relate to the representation in thedrawing and are used below synonymously with the “first” and “second”strip.

The upper strip 11 and the lower strip 12 are in each case composed ofseveral sections 10. The sections 10 of the upper strip 11 and the lowerstrip 12 are arranged offset with respect to one another, so that ineach case they overlap by half a section 10. One LED is connectedbetween the right-hand region (in the drawing) of a section 10 of theupper strip 11 and the left-hand region (in the drawing) of a section 10of the lower strip 12. A LED is likewise connected between theright-hand region (in the drawing) of a section 10 of the lower strip 12and the left-hand region (in the drawing) of a section 10 of the upperstrip 11, so that the LEDs are series-connected. This pattern continuesover the length of the leadframe 8. For reasons of clarity, not all ofthe LEDs 9 are shown. Thus the leadframe 8 here brings about a seriesconnection of all LEDs 9. A continuous strip for returning theelectrical connection is not provided.

An embodiment of a light fixture in which the leadframe 8 illustrated inFIG. 15 can be used is illustrated in part in FIG. 16. The leadframe 8is mounted on the inside of a tubular bulb 1 so that it extends from anopen end of the bulb 1 to a closed end of the bulb 1, extends along thefront face 25 there and subsequently extends from the closed end of thebulb 1 again to the open end of the bulb 1. Since both ends of theleadframe 8 lie at the open end of the bulb 1, they can be connectedthere to an electronic driver (not illustrated), without the need for acontinuous strip for returning the electrical connection.

Accordingly, the other leadframes described above can also be used ineach case without a continuous third strip in such a light fixture.

The leadframes 8 illustrated in FIGS. 9 to 15 can in each case beprovided with one or two end sections 19, 20 for electronic components 5of a driver 4, as illustrated in FIGS. 5 to 8.

FIGS. 17 to 20 illustrate by way of example how the end region or theend regions 19, 20 of a leadframe 8 can be divided into sections 10′ sothat the electronic components 5 of the driver 4 can be arrangeddirectly on the leadframe 8.

FIG. 17 shows a first end region 19 of the leadframe 8 schematically onthe left in the drawing. On the right in the drawing the central region18 of the leadframe is shown with three strips 11, 12, 13 (at the bottomin the drawing) of the light engine which in each case consist ofseveral sections 10.

FIG. 18 shows a second end region 20 of the leadframe 8 schematically onthe right in the drawing. On the left in the drawing the central region18 of the leadframe is shown with three strips 11, 12, 13 (at the bottomin the drawing) of the light engine which in each case consist ofseveral sections 10.

The two upper continuous strips 21 (the two upper strips in each case inFIGS. 17 and 18) serve for connection of the two driver sections, thecomponents 5 of which are arranged in the two end regions 19, 20 of theleadframe 8.

The sections 10, 10′ of the leadframe 8 are connected to one another byconnection bars 16 in FIGS. 17 and 18. These can be severed after theelectronic components 5 of the driver 4 are fastened on the leadframe 8.

In FIG. 19 a detail of a light fixture is shown schematically with aleadframe 8 on which the electronic components 5 of the driver 4 arearranged directly. The arrangement according to FIG. 19 without theelectronic components 5 of the driver 4 is illustrated in FIG. 20. Forthis purpose FIG. 20 shows how the leadframe 8 can be retained in aretaining bar 7 in the end region 19. FIG. 20 also shows the connectionbars 16 which connect the sections 10, 10′ of the leadframe 8 during theproduction.

Since the electronic components 5 of the driver 4 are usually arrangedon the leadframe 8 before the leadframe is installed in the lightfixture, FIG. 20 does not show a state which usually occurs during theproduction of the light fixture but serves merely for illustration.

Although the invention has been illustrated and described in greaterdetail by the depicted exemplary embodiments, the invention is notrestricted thereto and other variations can be deduced therefrom by theperson skilled in the art without departing from the scope of protectionof the invention.

In general “a” or “an” may be understood as a single number or amajority, in particular in the context of “at least one” or “one ormore” etc., provided that this is not explicitly precluded, for exampleby the expression “precisely one” etc.

Also, when a number is given this may encompass precisely the statednumber and also a conventional tolerance range, provided that this isnot explicitly ruled out.

If applicable, all individual features which are set out in theexemplary embodiments can be combined with one another and/or exchangedfor one another, without departing from the scope of the invention.

LIST OF REFERENCES

-   1 tubular bulb-   2 end cap-   3 connecting pin-   4 electronic driver-   5 electronic components of the electronic driver-   6 printed circuit board of the electronic driver-   7 retaining bar-   8 leadframe-   9 LED-   9′ LED-   10 section of the leadframe-   10′ section of the leadframe-   11 first strip of the leadframe-   12 second strip of the leadframe-   13 third strip of the leadframe-   14 U-shaped contact regions-   15 sheet-   16 connection bars-   17 frame-   18 central region of the leadframe-   19 first end region of the leadframe-   20 second end region of the leadframe-   21 further strips of the leadframe-   22 depressions-   23 cable-   24 stabilizing section-   25 end face-   26 contact clip-   27 connection region of the contact clip-   D diodes of the rectifier-   C1 smoothing capacitor-   C2 capacitor-   R1 resistor-   R2 resistor-   IC integrated circuit

What is claimed is:
 1. A tubular lamp comprising: a light enginedisposed within the tubular lamp, the light engine comprising: aleadframe configured as an electrically conductive structure that lacksan electrically insulating substrate or an electrically insulatingflexible layer; and at least one semiconductor light element arranged onthe leadframe; and a printed circuit board (PCB) disposed within thetubular lamp and electrically connected to the leadframe by at least oneelectrically conductive contact clip that electrically contacts the PCB.2. The tubular lamp of claim 1, wherein the at least one electricallyconductive contact clip electrically contacts a surface of the leadframeand curves around an end of the PCB to electrically contact the PCB. 3.The tubular lamp of claim 1, wherein the at least one electricallyconductive contact clip has a first region of substantially U-shapedgeometry that fits onto the PCB.
 4. The tubular lamp of claim 3, whereinthe at least one electrically conductive contact clip has a secondregion of substantially planar geometry that extends from the firstregion between the PCB and the leadframe.
 5. The tubular lamp of claim1, wherein: the PCB has a first upper surface and a first lower surfacethat opposes the first upper surface; the leadframe has a second uppersurface and a second lower surface that opposes the second uppersurface; and the at least one electrically conductive contact clipelectrically contacts the first upper surface of the PCB and the secondupper surface of the leadframe.
 6. The tubular lamp of claim 1, whereinthe at least one electrically conductive contact clip is a componentphysically distinct from both the leadframe and the PCB.
 7. The tubularlamp of claim 1, wherein the at least one electrically conductivecontact clip comprises a first electrically conductive contact clip anda second electrically conductive contact clip which are componentsphysically distinct from one another.
 8. The tubular lamp of claim 1,wherein at least one of: the leadframe is configured as an elongate,substantially planar structure; and the leadframe is formed as aplurality of electrically conductive tracks situated so as to at leastpartially overlap in length adjacent one another.
 9. The tubular lamp ofclaim 1, wherein within the tubular lamp, the leadframe and the PCB areoffset from one another such that the leadframe and the PCB at leastpartially overlap in length.
 10. The tubular lamp of claim 1, furthercomprising an electronic driver electrically connected with the at leastone semiconductor light element, the electronic driver comprising: afirst electronic component arranged on the leadframe; and a secondelectronic component arranged on the PCB.
 11. A tubular lamp comprising:a light engine disposed within the tubular lamp, the light enginecomprising: a leadframe configured as an electrically conductivestructure that lacks an electrically insulating substrate or anelectrically insulating flexible layer; and at least one semiconductorlight element arranged on the leadframe; and a printed circuit board(PCB) disposed within the tubular lamp and electrically connected to theleadframe by at least one portion of the leadframe which is bent into atleast one electrically conductive contact region that electricallycontacts the PCB.
 12. The tubular lamp of claim 11, wherein the at leastone electrically conductive contact region curves around an end of thePCB to electrically contact the PCB.
 13. The tubular lamp of claim 11,wherein the at least one electrically conductive contact region has asubstantially U-shaped geometry that fits onto the PCB.
 14. The tubularlamp of claim 13, wherein in being so bent, the at least one portion ofthe leadframe doubles back over another portion of the leadframe. 15.The tubular lamp of claim 11, wherein: the PCB has a first upper surfaceand a first lower surface that opposes the first upper surface; theleadframe has a second upper surface and a second lower surface thatopposes the second upper surface; and the at least one electricallyconductive contact region electrically contacts the first upper surfaceof the PCB and the second lower surface of the leadframe.
 16. Thetubular lamp of claim 11, wherein the at least one electricallyconductive contact region comprises a first electrically conductivecontact region and a second electrically conductive contact region whichare portions of the leadframe physically distinct from one another. 17.The tubular lamp of claim 11, wherein the leadframe is made from amaterial having spring characteristics that ensure the at least oneelectrically conductive contact region of the leadframe presses againstthe PCB.
 18. The tubular lamp of claim 11, wherein at least one of: theleadframe is configured as an elongate, substantially planar structure;and the leadframe is formed as a plurality of electrically conductivetracks situated so as to at least partially overlap in length adjacentone another.
 19. The tubular lamp of claim 11, wherein within thetubular lamp, the leadframe and the PCB are offset from one another suchthat the leadframe and the PCB at least partially overlap in length. 20.The tubular lamp of claim 11, further comprising an electronic driverelectrically connected with the at least one semiconductor lightelement, the electronic driver comprising: a first electronic componentarranged on the leadframe; and a second electronic component arranged onthe PCB.